Ratchet starter for motors



March 7, 1950 A. A. HONEYMAN RATCHET STARTER FOR MOTORS 2 Sheets-Sheet 1Filed Sept. 21, 1948 INVENTOR. Ari/7w A. Honey/77cm %wz4mw mam fife/waysMarch 7, 1950 A. A. HONEYMAN RATCHET STARTER FOR MOTORS 2 Sheets-Sheet 2Filed Sept. 21, 1948 INVENTOR.

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Patented Mar. 7, 1950 RATCHET STARTER FOR MOTORS Arthur Alan Honeyman,Portland, reg., assignor to G. S. Hinsdale, Portland, Oreg.

Application September 21, 1948, Serial N 0. 50,398

7 Claims. (01. 74140) The present invention comprises a starting devicefor internal combustion engines, particularly engines of the type havingan end of an engine shaft projecting from the crankcase. The engineshaft in such case is usually the crankshaft to which the pistons areconnected, but it is to be understood that the invention is not limitedto connection to a crankshaft as it may be connected to an auxiliaryshaft which in turn is geared to or otherwise driven by the crankshaft.

The present invention is of greatest utility in small industrialequipment such as portable chain saws, tree drilling equipment, or othersimilar equipment for which it is impractical or inconvenient to supplyelectric starting equipment. An example of an other than industrialmachine to which the present invention might be applied is in outboardmotor for propelling boats.

In the field of greatest utility, namely in portable industrialequipment, it is imperative that the starting equipment should be assturdy as possible, hence the starting device preferably comprises astarting pulley adapted to be connected to the engine shaft and a wirerope, cable or other durable, flexible element adapted to be wrappedabout the pulley. When a wire rope or cable is so employed a backfire orseries thereof may retract the flexible element until the hand gripthereon is jammed against the housing of the starting device withresulting breakage of the equipment or, in the event the operator hasnot released the hand grip, with resulting injury to his hand. Theprincipal object of the present invention is to provide a startingdevice of the character described in which damage to the equipment orinjury to the operator is positively prevented in the event of reverserotation of the engine shaft due to backflring.

A further object of the present invention is to provide a sturdymechanism of the character described which may be manufactured ofrelatively few, easily formed and assembled parts.

The foregoing objects and advantages of the present invention will bemore readily understood by reference to the following specificationtaken in connection with the accompanying drawing wherein like numeralsrefer to like parts throughout, while the features of novelty will bemore distinctly pointed out in the appended claims.

In the drawings- Fig. 1 is a horizontal section taken through a 56 Ipin. The opposite end of the spiral spring 38 preferred form of thedevice substantially along line l-l of Fi 2;

Fig. 2 is a vertical section thereof taken substantially along the line2--2 of Fig. 1;

Fig. 3 is a horizontal section taken substantially along line 33 of Fig.2; and

Fig. 4 is a horizontal section taken substantially along the line 4-4 ofFig. 2, but showing certain parts in another relation to each other.

The device is herein illustrated as comprising a housing including abase section It and an outer section including an end wall II and asubstantially cylindrical side wall l2, the two sections being united byproviding a flange M on the base section Ill adapted to fit within thecylindrical wall I2 and be attached thereto by screws [5. The basesection [0 is adapted to be 1 attached to the crankcase of an engine bymeans of screws l6 for which threaded openings are provided in a portionof the crankcase I! of the engine. The crankshaft or connected engineshaft 18 is provided with an end projecting through a central opening inthe base section [0.

The starting device comprises a driven part, in this instance a toothedratchet wheel 20. The ratchet wheel 20 comprises a hub portion, thecentral part of which is provided with a stepped bore, into the base ofwhich a reduced intermediate portion 2| on the shaft is inserted andretained by a key 22. The tip of the shaft is provided with a reducedthreaded portion 23 on which a nut 24 is mounted to retain a washer 25extending over the stepped base portion of the v bore in the hub of theratchet wheel and thus locking the wheel 20 and key 22 in position. Theratchet wheel is provided. with a plurality of ratchet teeth all facingin a direction such that a ratchet pawl may drive the shaft 18 in thedirection of normal rotation.

The starting mechanism comprises a driving assembly including a pullcord 30, a pulley 3! about which the pull cord may be wrapped, and

a ratchet pawl 32 mounted upon the pulley in position to engage theteeth of the ratchet Wheel. The pulley 3| is mounted upon a bolt 33extending coaxially of the shaft [8 through an opening in the end wallH, there preferably being provided a ball-bearing assembly 34 to reducefriction. The pull cord 30 is wrapped about the sheave portion of thepulley several times, and its inner end extends through an opening inthe wall of the sheave and terminates in a knot or other enlargement 35which is situated in a countersink 3B in the outer face of the pulley.

A pin 3'! projects downwardly from the sheavev is hooked into a slot ina flange on the base section in surrounding the hub of the ratchet wheel28. The spiral spring is so connected between'the housing and the pulleyas to be tensioned when the pull cord 30 is pulled from the housing,thereby providing means for retracting the pull cord into the housing.

The outer end of the pull cord is adjustably affixed to a pull gripincluding a body 4| of soft or resilient material such as rubber or theequivalent. The cord extends through a central opening in the body 4|and a central opening in a metallic plug 42 seated in a depression inthe outer surface of the body. The plug is provided with a secondopening 43 into which the extreme end of the pull cord may be inserted,and the plug is also provided with a threaded opening for reception of ascrew 44. A washer 45 preferably surrounds the outer end of the stem ofthe screw. The screw is so positioned relative to adjacent portions ofthe pull cord that tightening thereof causes the washer 45 to spread andjam the ends of the pull cord to prevent slippage thereof relative tothe body 4| The pull cord extends tangentially from the pulley throughan opening 46 in the side wall 12, and the side wall i2 is provided witha tangentially extending projection in which a communicating, tangentialpassage 47 is provided. The passage 4'! slidably guides a tubular guide50 fixed to the outer end of a pawl releasing device and having its endprojecting into the outer end of the passage 41. A cap 5| is retained onthe outer end of the tubular guide by a screw 52, the cap being providedwith a central opening through which the cable 30 extends. The outer endof the guide 50 is reduced in diameter for reception of the cap 5! and avertically extending ring 53 is clamped between the cap and the shoulderof the reduced portion. The ring 53 is integral with a bar 54 which isslidably guided between flanges ,55 and 56 on the upper part of thehousing projection and slidably extends through a slot in the side walll2 adjacent the opening 46. The inner end of the bar 54 has an armthereon which carries a .pivot pin 60, the pin being pivotally attachedto the free end of a movable pawl shifting cam 61 which is pivotallymounted on a stud 62 extending inwardly from the end wall H. the shapeof a half-moon and the inner surface thereof surrounds a boss on the endWall H in which the bearing 34 is mounted. A cam spring of the wishbonetype, comprising one leg 33 bearing against the inner end of the bar 54and a second leg 64 retained in a notch 65 in the side wall i2, ismounted upon the housing by a stud 66 extending inwardly from the endwall H and having a large head 61 to retain the legs of the springagainst the end wall H. The cam spring therefore acts normally to holdthe cam Bl in the position illustrated in Figs. 1 and 2, and also tohold the cam shifting bar 54 in the extended position illustrated inFigs. 1, 2 and 3 in which the ring portion 53 is spaced from the end .ofthe housing projection.

The ratchet pawl 32 is pivotally mounted upon a pivot Til projectingbelow the pulley 3i A portion of the ratchet pawl .32 is positioned .soas to be engageable by the cam 6!, the portion in the presentillustration comprising a pin 1 l projecting through an opening 12 inthe pulley 3|. A wire spring 13 is mounted upon a stud 14 having anenlarged head to retain the wire spring against the inner surface of thepulley. One end The cam BI is substantially in of the wire spring isretained in a slot in the free end of the ratchet pawl 32 and the otherend is retained in a small hole drilled into the flange of the pulley,the intermediate portion of the wire being wrapped around the stem ofthe stud. The wire spring therefore constitutes a ratchet pawl spring soarranged as to urge the ratchet pawl into engagement with the ratchetwheel. When the pawl is so engaged the pin 'H is toward the inner sideof the hole 12 through the pulley. If the cam (ii is shifted outwardly,a portion thereof will engage the pin H to move the pawl against thetension of spring 13 until the pin H strikes the outer side of theopening 12. When so moved the pawl is heldfree of the ratchet wheel sothat backfiring of the engine causing reverse rotation of the shaft l8will not cause continued rewinding rotation of the pulley 3|.

In order that the pawl may be disengaged at the proper time, the lengthof cable 36 from its point of attachment to the pulley to the innersurface of the hand grip body 41 must be fixed within limits such thatthe movement of cam 5! will disengage the ratchet pawl when the cable isfully retracted. In order that the device may be assembled with the handgrip in proper relation to the cable, the ratchet wheel is mounted upontheend of the shaft after the section 10 of the housing is mounted inits proper position, the spring 38 is assembled to the driving portionof the starting mechanism which is mounted in the outer section of thehousing, and the two parts of the housing are slipped together whilemaking certain that the inner end of the spring is hooked into the slotin the flange 40. A. certain amount of initial tension is imposed uponthe spring 38 by rotating the outer housing section in a direction totighten the spring before inserting the screws 15. As soon as sumcientinitial tension has been imposed upon the spring the pulley is arrestedwith the countersink opening 36 beneath an opening 8.0 in end wall 1 l.The opening is adjacent the inner end of the passage 41 so that the endof the cable 30 may be slipped through the opening in the flange of thepulley and projected through the passage 4? until the knot 35 is drawntightly against the bottom of the countersink 36. The tension of thespring 36 is sufficient to cause .the cable to be drawn onto the pulleyfor the desired distance corresponding to the distance which the cablemay be moved when manually pulled in the starting action with sufiicientadditional tension to overcome the force of the cam spring and the pawlspring. The

; projecting end of the cable 30 is now slipped through the grip body 4|and anchored to the plug 42 as previously described. With the remainingtension of the :spring exerted against the hand grip in engagement withthe outer end of the shifting bar the cam is moved outward to theposition seen in Fig. 4. The length of the cable is fixed such that theoutward movement of cam 6| occurs when the pin H on the pulley isadjacent or .close to the movable end of the cam in order to insuresufficient movement of the ratchet pawl. outer edge of the opening 12the ring portion '53 will be adjacent the end of the housing projection.It is to be remarked that the length of the cam 6| having sufiicientmovement to disengage the ratchet pawl is so great that in the event thefingers of the operator are caught between the body 4| and the .outerendof the cap 5!, the bar 54 will be moved inwardly after the pin H hasmoved beyond the pivot 69. Th camspring will When the pin H strikes the.

hold the cam in inoperative position at all other times, but it is to beobserved that someone might manually move the bar 54 inward when the pinH is on the side opposite the cam (ii. In order to prevent damage fromoccurring as a result of the pin l'l striking the end of the cam 5!adjacent pivot 60 in such event, the outer corner thereof is preferablycut away so as to provide a cam surface which will insure engagement ofthe pin with the outer surface of the cam.

The guiding portions of the cam shifting mechanism comprising theportion of the bar El i engaged between the flanges 55 and 5t and thetubular guide 50 engaged in the passage 4? are loosely fitted to allowslight pivotal movement of the inner end of the bar as the cam swingsabout the stud 62. It is also to be appreciated that the bar 54 may takother forms than that herein illustrated and that the arrangement of themechanism, as well as the proportion and I design of the particularparts, may be waried while still retaining the essence of the invention.All such modifications in arrangement and detail as come within thepurview of the appended claims are considered to be a part of myinvention.

I claim:

1. A starting device for an internal combustion engine having an end ofan engine shaft projecting from the crankcase, comprising a drivingassembly adapted to be mounted on the crankcase and including apull-cord having a handgrip fixed thereto, a pulley rotated by thepull-cord spring return means therefor, a driven part adapted to bemounted on the engine shaft, a pawl normally connecting said drivingassembly to said driven part for rotation in the normal direction ofengine shaft rotation when said pull-cord is pulled, and a pawlreleasing device including a movable part engageable by said handgripfor disconnecting said driving assembly from said driven part in theevent of complete rewinding of said pull-cord on said pulley.

2. A starting device for an internal combustion engine having an end ofan engine shaft projecting from the crankcase, comprising a drivingassembly adapted to be mounted on the crankcase and including apull-cord having a handgrip at its free end, a pulley rotated by thepull-cord and spring return means therefor, a driven part adapted to bemounted on the engine shaft, a pawl normally connecting said drivingassembly to said driven part for rotation in the normal direction ofengine shaft rotation when said pull-cord is pulled, and a pawlreleasing device including a movable part engageable by said hangrip orthe pulling hand of the operator and a pawl-engaging cam connected tosaid movable part for disconnecting said driving assembly from saiddriven part in the event of reverse rotation of said engine shaft due tobackfiring.

3. A starting device for an internal combustion engine having an end ofan engine shaft projecting from the crankcase, comprising a housingadapted to be secured to the crankcase in position to enclose theprojecting end of the engine shaft and having an opening through theside thereof, a ratchet wheel adapted to be secured to the end of theengine shaft, a pulley mounted within said housing, a flexible elementattached to said pulley at one end and having its other end projectingthrough said opening, a spiral spring having one end secured to saidpulley and its other end secured to said housing in such manner as tocause winding of said flexible element onto said pulley, a pull grip onthe free end of said flexible element, a ratchet pawl pivotally mountedon said pulley in position to engage the teeth of said ratchet wheel, apawl spring mounted on said pulley and urging said ratchet pawl towardengaging position whereby manual withdrawal of said flexible elementcauses rotation of the engine shaft, and pawl releasing means mounted onsaid housing, said means comprising a cam movably mounted on saidhousing, a cam spring normally urging said cam toward an inoperativeposition, a movable cam shifter extending through said housing adjacentsaid opening and engaged with said cam at its inner end, and a guide onthe outer end of said cam shifter through which said flexible elementextends, said cam shifter upon inward movement thereof causing movementof said ratchet pawl to a position such as to engage said ratchet pawland force it from engagement with the teeth of said ratchet wheel.

A starting device for an internal combustion engine having an end of anengine shaft projecting from the crankcase, comprising a housing adaptedto be secured to the crankcase in position to enclose the projecting endof the engine shaft and having an opening through the side thereof, aratchet wheel adapted to be secured to the end of the engine shaft, apulley mounted within said housing, a flexible element attached to saidpulley at one end and having its other end projecting through saidopening, a spiral spring having one end secured to said pulley and itsother end secured to said housing in such manner as to cause winding ofsaid flexible element onto said pulley, a pull grip on the free end ofsaid flexible element, a ratchet pawl pivotally mounted on said pulleyin position to engage the teeth of said ratchet wheel, a pawl springmounted on said pulley and urging said ratchet pawl toward engagingposition whereby manual withdrawal of said flexible element causesrotation of the engine shaft, and pawl releasing means mounted on saidhousing, said means comprising a cam movably mounted on said housing, acam spring normally urging said cam toward an inoperative position, amovable cam shifter extending through said housing adjacent said openingand engaged with said cam at its inner end, and a guide on the outer endof said cam shifter through which said flexible element extends, saidguide being restricted to prevent passage of said pull grip wherebywinding of said flexible element onto said pulley until said pull gripengages said guide and moves said cam shifter causes movement of saidcam into disengaging relation to said ratchet pawl.

5. A starting device for an internal combustion engine having an end ofan engine shaft projecting from the crankcase, comprising a housingadapted to be secured to the crankcase in position to enclose theprojecting end of the engine shaft and having an opening through theside thereof, a ratchet wheel adapted to be secured to the end of theengine shaft, a pulley mounted within said housing, a flexible elementattached to said pulley at one end and having its other end projectingthrough said opening, a spiral spring having one end secured to saidpulley and its other end secured to said housing in such manner as tocause winding of said flexible element onto said pulley, a pull grip onthe free end of said flexible element, a ratchet pawl pivotally mountedon said pulley in position to engage the teeth of said ratchet wheel, apawl spring mounted on said pulley and urging said ratchet pawl towardengaging position whereby manual withdrawal of said flexible elementcauses rotation of the engine shaft, and pawl releasing means mounted.on said housing, said means comprising a cam pivotally mounted on saidhousing, a cam shifter pivotally attached to said cam and including anextension projecting through the side of the housing in position to beengaged by said pull grip upon movement of said pulley in the directioncausing winding of said flexible element thereon, and a cam springbiased between said cam shifter and said housing to hold said cam out ofthe path of rotation of said ratchet pawl and to hold said cam shifterin a position such that said extension projects from said housing to itsfullest extent, said cam being arranged to project into the path of aportion of said ratchet pawl upon inward movement of said cam shifteragainst the force of said cam spring.

6. The combination disclosed in claim 5 wherein said cam is mountedadjacent the outer surface of said pulley, said ratchet pawl is mountedupon the inner surface of said pulley, said pulley is provided with anopening therethrough adjacent said ratchet pawl, and the portion of saidratchet pawl engageable by said cam comprises a pin projecting throughsaid opening.

7. The combination disclosed in claim 5 wherein said housing comprises aportion having a passage therein communicating with said opening, andsaid extension comprises a tubular guide slidably extending into theouter end of said passage and through which said flexible elementextends.

ARTHUR ALAN HONEYMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,099,685 Bennett June 9, 19142,204,750 Conover June 18, 1940 2,348,547 Kissel May 9, 1944

